Exhaust emissions from automotive vehicles are sometimes tested on production vehicles temporarily retrieved from an owner for performance of “in-use” testing. Some regulatory tests require that the vehicle be operated within a sealed shed, with the total emissions in the shed being monitored. Other tests may require emissions be captured at the tailpipe (also referred to as an exhaust pipe).
In order to mate the tailpipe with typical test measurement devices on current diesel exhaust systems, the passive exhaust cooler (PEC) is cut from the exhaust pipe, a flange is welded at the point of the cut, and a flanged tailpipe extension with a coupling flange is then bolted to the welded flange. The coupling flange may be a flange such as is available from Marmon-Herrington Company, Louisville, Ky., and that is commonly referred to as a Marmon flange by those skilled in the art. The diesel exhaust testing unit is then coupled to the Marmon flange. At the conclusion of testing, the tailpipe must be replaced, and a PEC connected to the tailpipe to return the vehicle to production configuration prior to returning the vehicle to the owner.